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1.
Tertiary N-ethylamines were converted into amide derivatives by reactions with sulfur monochloride and DABCO at 0 °C. Depending on the
nature of the substituents in the amine, the reaction can be accompanied by unexpected transformations.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1135–1140, June, 2007. 相似文献
2.
G. R. Kosmambetova P. E. Strizhak É. M. Moroz T. E. Konstantinova A. V. Gural’skii V. P. Kol’ko V. I. Gritsenko I. A. Danilenko O. A. Gorban 《Theoretical and Experimental Chemistry》2007,43(2):102-107
The morphological and catalytic properties of samples of nanomeric zirconium dioxide, stabilized with yttrium oxide, manufactured
via the effect of a UHF field during the process of drying precipitated zirconium hydroxide and calcination at temperatures
from 300 to 1000 °C, were studied. It was shown that the highest activity in the oxidation of CO occurred with 40 nm particles
of zirconium dioxide prepared at 1000 °C.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 2, pp. 96–101, March–April, 2007. 相似文献
3.
Konstantinova T. V. Klykov V. N. Maslov M. A. Serebrennikova G. A. 《Russian Journal of Organic Chemistry》2002,38(8):1189-1191
Syntheses of N,N,N-trimethyl[2-(3-cholesteryloxy)syccinyloxyethyl]ammonium iodide, N,N-dimethyl-N-2-hydroxyethyl[2-(3-cholesteryloxy)syccinyloxyethyl]ammonium iodide, and N-[(3-cholesteryloxy)syccinyl]piperazine were performed. The compounds synthesized in a liposomal form may be used for delivery of genetical material into cells. 相似文献
4.
Amelichev SA Aysin RR Konstantinova LS Obruchnikova NV Rakitin OA Rees CW 《Organic letters》2005,7(25):5725-5727
[chemical reaction: see text]. Treatment of N-substituted 2,5-dimethylpyrroles 2 with an equilibrated mixture of disulfur dichloride and DABCO in chloroform at 0 degrees C gives pentathiepinopyrroles 3 in moderate yields; further reaction of 3 with the same mixture at room temperature leads, in an extensive reaction cascade, to bis(dithiolo)pyrroles 4 in high yield; 2 can be converted into 4 in a one-pot operation under unusually mild conditions. 相似文献
5.
Yu. I. Dikanskii O. A. Nechaeva A. R. Zakinyan N. Yu. Konstantinova 《Colloid Journal》2007,69(6):691-694
Structural transformations and relevant changes in the magnetic and optical properties of magnetosensitive emulsions based on magnetic fluids are experimentally studied. Peculiarities of the changes in the magnetic susceptibility of emulsions associated with the deformation of their microdroplets and the effect of phase inversion (the transformation of dispersions of magnetic droplets in nonmagnetic media into dispersions of nonmagnetic droplets in magnetic fluids) are established. Optical effects occurring in magnetic emulsions under the combined action of a shear flow and a magnetic field are studied. It is concluded that optically active composition media may be developed on the basis of magnetic fluids. 相似文献
6.
It was shown that two series of products with opening and with preservation of the aromatic nucleus are formed in the reaction of ozone with ionol, and a mechanism was proposed for the reaction.N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 117334 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 5, pp. 1203–1207, May, 1992. 相似文献
7.
Eight series of molecular structures represented by molecular hypergraphs and molecular graphs are considered. A comparative
analysis is performed for 23 integral topological and information theoretical indices for the graph and hypergraph models.
For each series, the sensitivity is studied on both models, correlations are established for indices inside the models, and
indices not correlating with each other are found. The results of this analysis showed that the sensitivity of most indices
is higher in the hypergraph model. The total number of noncorrelated indices also increases in the latter model.
Translated fromZhurnal Struktumoi Khimii, Vol. 39, No. 6, pp. 1163–1171, November–December, 1998. 相似文献
8.
N. N. Konstantinova M. A. Magomedov V. Yu. Rud' Yu. V. Rud' 《Russian Physics Journal》1992,35(2):120-121
We have studied the photoelectric properties of the potential barrier which arises at the interface between an electrolyte and thin n-CuInSe2 films deposited on glass by vacuum evaporation. Photoelectrochemical cells were used to observe the rectification and photosensitivity near the fundamental absorption of CuInSe2 for photon energies >1 eV. It was found that there is a correspondence between the spectral dependence of the absorption and the photosensitivity of the cells, which indicates a constant quantum efficiency for the photoconversion process. We conclude with a discussion of the practical application of the potential barriers studied.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 24–26, February, 1992. 相似文献
9.
Dr. Vladimir V. Shilovskikh Alexandra A. Timralieva Pavel V. Nesterov Dr. Alexander S. Novikov Dr. Petr A. Sitnikov Prof. Elizaveta A. Konstantinova Prof. Alexander I. Kokorin Prof. Ekaterina V. Skorb 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(70):16603-16610
In the last two decades, a large number of self-assembled materials were synthesized and they have already found their way into large-scale industry and science. Hydrogen-bond-based supramolecular adducts are found to have unique properties and to be perfect host structures for trapping target molecules or ions. Such chemical systems are believed to resemble living matter and can substitute a living cell in a number of cases. Herein, a report on an organic material based on supramolecular assembly of barbituric acid and melamine is presented. Surprisingly, the structure is found to host and stabilize radicals under mild conditions allowing its use for biological applications. The number of free radicals is found to be easily tuned by changing the pH of the environment and it increases when exposed to light up to a saturation level. We describe a preparation method as well as stability properties of melamine–barbiturate self-assembly, potentiometric titration, and hydrogen ions adsorption data and EPR spectra concerning the composite. 相似文献